From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Date: Mon, 29 Dec 2014 20:17:26 +0100 Subject: [U-Boot] L2 cache and LCD on sunxi In-Reply-To: References: <54984A91.1040708@redhat.com> <549AEE10.60706@redhat.com> Message-ID: <54A1A8C6.3020303@redhat.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi, On 29-12-14 17:23, Simon Glass wrote: > Hi Hans, > > On 24 December 2014 at 09:47, Hans de Goede wrote: >> Hi, >> >> On 23-12-14 05:36, Simon Glass wrote: >>> >>> Hi Hans, >>> >>> On 22 December 2014 at 09:45, Hans de Goede wrote: >>>> >>>> Hi, >>>> >>>> On 21-12-14 19:52, Simon Glass wrote: >>>>> >>>>> >>>>> Hi, >>>>> >>>>> I ran up a banana PI and noticed that HDMI works in U-Boot. Great! >>>>> >>>>> Scrolling seems very slow though - is the L2 cache disabled perhaps? >>>> >>>> >>>> >>>> I don't think so, but it could be, I think the scrolling code is just >>>> very inefficient. Feel free to poke things a bit around this, ARM >>>> cache management is not my forte. >>> >>> >>> I think it need ssomething like the code in exynos/soc.c - see >>> v7_outer_cache_enable(). >>> >>> Even with the 7 inch it's very slow. >> >> >> I've run some tests, and it is not slower then on say the A10 (cortex A8), >> also I've been unable to find any docs or allwinner code pointing to >> allwinner specific l2 cache init. As such ATM I do not believe that we've >> the l2 cache disabled. > > Yes the code is not super-efficient (and could use the arch-specific > memcpy()) but I'm mostly interested in whether the platform is running > at full speed. > > I'm comparing it to say an Exynos 5250 which is 1.7GHz Cortex-A15. > Without the L2 cache it scrolls quite slowly but with it it is fast. Well this is a 1 GHz Cortex A7, and one with likely a much less efficient DRAM controller / less DRAM bandwidth. > There is probably some cache setup required. That could be, but if that is the case then I don't know where to start looking for it. I certainly cannot find any such thing in allwinner;s boot0 / boot1 bootloader. Regards, Hans